Character Association and Path Coefficient Analysis for Early Seedling Vigour Traits in rice (Oryza sativa L.)
Rakshitha V. *
Department of Genetics and Plant Breeding, College of Agriculture, PJTSAU, Hyderabad, Telangana, India and Indian Council of Agricultural Research (ICAR), Indian Institute of Rice Research (IIRR), Rajendranagar, Hyderabad, Telangana, India.
J. Suresh
Department of Genetics and Plant Breeding, College of Agriculture, PJTSAU, Hyderabad, Telangana, India.
C. Narendra Reddy
Department of Entomology, College of Agriculture, PJTSAU, Hyderabad, Telangana, India.
Channappa Gireesh
Indian Council of Agricultural Research (ICAR), Indian Institute of Rice Research (IIRR), Rajendranagar, Hyderabad, Telangana, India and Indian Council of Agricultural Research (ICAR), Indian Institute of Seed Science (IISS), Regional Station, Bengaluru, Karnataka, India.
*Author to whom correspondence should be addressed.
Abstract
Early seedling vigour, a key trait in rice cultivation, significantly impacts plant establishment, growth and yield. The study applies path analysis to assess various rice traits and their direct and indirect contributions to early seedling vigour aiming to enhance breeding strategies for resilient rice varieties. A total of 168 rice genotypes from the 3K rice panel were evaluated for early seedling vigour traits under laboratory conditions. Key traits measured included germination percentage, seedling length, shoot length, root length, total fresh weight and total dry weight at 7 days after keeping for germination. Correlation studies showed germination percentage, seedling length, shoot length, root length, total fresh weight and total dry weight traits had significantly positive relationships with seedling vigour indices I and II. Path coefficient analysis identified positive direct effect on seedling vigour index I was exerted by germination percentage, seedling length, root length, shoot length and total dry weight and negative direct effect by total fresh weight. In case of Seedling vigour index II, positive direct effect was exerted via germination percentage, shoot length and total dry weight and negative direct effect via seedling length, root length and total fresh weight. Path results highlighted that, total dry weight as the most crucial trait with the highest positive effects on seedling vigour index II. Our findings indicate that selecting for these traits can effectively improve early seedling vigour in rice hybrids, aiding in the development of superior rice varieties for direct seeded condition.
Keywords: 3k RGP, early seedling vigour, correlation, path analysis, direct-seeded rice